Why is this a turning point in U.S. history?

Hiroshima and Nagasaki

In August 1945 The United States exploded a bomb over Hiroshima and Nagasaki, Japan. This was during the final stages of World War 2. The decision to use the Atomic Bomb was made by President Truman, this is one of the only times that the atomic bomb has been used during war time to this day. The bombs almost erased Hiroshima and Nagasaki from existence and showed the destructive force of these weapons. There were also some long-term results on humans and the environment from their use. Powerful leaders everywhere recognize that the possession of nuclear bombs is a symbol of national power and seem to agree that the actual use of the bomb is not necessary.

World War 2 Deaths Chart

On the left is a graph showing the breakdown among countries of total deaths and also shows who were allies and who were not ("Axis"), As seen, the Soviet Union, China, Poland, and Germany have the highest amount of deaths. The United States had less than a million deaths.Also, more Allied Civilians died than Axis Military, Axis Civilians, and Allied Military put together.The total amount of deaths is roughly 60 million people. It was roughly 20 million soldiers and 40 million civilians.